1-(Hetero)aryl-2,2,2-trichloroethanols are useful key intermediates for the synthesis of various bioactive compounds. Herein, we describe N-heterocyclic carbene (NHC)-coordinated cyclometallated palladium complex (CYP)-catalyzed (hetero)aryl addition of chloral hydrate using (hetero)arylboroxines, providing a new approach to 1-(hetero)aryl-2,2,2-trichloroethanols. Notably, PhS-IPent-CYP which coordinated
structurally diverse γ‐functionalized carboxylic acid derivatives in moderate to good yields. The precise chemoselectivity of the reaction among multiple alkene units even in the presence of reactive terminal alkenes highlights the unique catalytic features of manganese catalyst, and the excellent functional group compatibility of primary amides further complements other transition metals.
The nickel-catalyzed cross-coupling of bromodifluoromethylphosphonates with arylboron reagents was developed with a 1,10-phenanthroline-type ligand. In this process, functionalized and heterocycle-containing boroxines were found to be suitable partners, and the catalytic modification of biologically active molecules, such as fenofibrate and indomethacin, was also successfully achieved. Furthermore
Enantiospecific, Nickel-Catalyzed Cross-Couplings of Allylic Pivalates and Arylboroxines
作者:Harathi D. Srinivas、Qi Zhou、Mary P. Watson
DOI:10.1021/ol5016724
日期:2014.7.3
We have developed an enantiospecific, nickel-catalyzed cross-coupling of unsymmetric 1,3-disubstituted allylic pivalates with arylboroxines. The success of this reaction relies on the use of BnPPh2 as a supporting ligand for the nickel(0) catalyst and NaOMe as a base. This method shows excellent functional group tolerance and broad scope in both the allylic pivalate and arylboroxine, enabling the preparation of 1,3-diaryl allylic products in high yields with excellent levels of regioselectivity and stereochemical fidelity.